Percolation Test

This is simple test to determine the water absorption rate of your soil.

• Uses: Septic designs, wells, building structures, garden planning

Procedure

• Dig a hole about 1.5 feet deep. You want to be below the top soil

• If this is for septic system it is recommended to dig the same depth as the proposed bed

• Pour a few buckets of water in the hole over a 24 hour period. You want the soil to be saturated

• During this part you can take readings if you like but the next ones are the ones that count

• After 24 hours, fill the hole with water. Put a measure tape or ruler in the hole. We recommended it is left there untouched for the duration

• Take reading of water level every 10 mins

Results

• Take the total amount of the level drop. Divide by 60 mins. That is your T time.

• T – 5 or less is typically for sandy soil

• T-50 or more is for heavy clay soil

• Depending on the project, we recommend additional test for more details about soil conditions such as sieve test and ribbon test